There is a need for a simple and durable signal device to alert patrons to the presence of mail. The present invention relates to a mail-call signal device for use on rural and curbside mailboxes to alert the patrons that mail has been received, thereby rendering it unnessary for them to waste valuable time by walking to an empty mailbox. In addition, because rural mailboxes are mounted with the view of the door either facing or not facing the line of sight of the patron, it is important that the mail-call signal device be visible from the front or back view.